1. Field of the Invention
The invention concerns an apparatus for wirelessly transmitting the temperature and an identifying characteristic of a cooking pot placed on one of the cooking zones of a stove to an electronic transmitting-receiving arrangement of the stove.
2. Discussion of the Prior Art
An apparatus of that kind is described in DE 32 25 386 A1. It serves for controlling the power of the respective cooking zone, in accordance with the respective need involved. DE 32 25 486 A1 discloses the provision on a cooking pot of a measuring station which radiates to an interrogation station temperature signals corresponding to the temperature of the cooking pot or the item being cooked. Besides the measurement value, the measuring station can also transmit an identification characteristic. The operating energy for the active transmitting portion of the measuring station is obtained from a microwave energy field which is radiated by the interrogation station. If the measuring station which is to be mounted to the cooking pot or the lid thereof is implemented in a practical context, the measuring station is already comparatively large for the simple reason that it requires a temperature sensor and a circuit which takes electrical energy from the energy field and stores it in order to emit measurement signals by way of the active components. Problems also occur in regard to washability of the cooking pot, in particular if it is intended to be cleaned in a washing machine.
The interrogation station of DE 32 25 486 A1 is to be arranged above the stove, for example in an extractor hood. It is therefore necessary to provide an external connection to the stove control assembly. That makes installation expensive and involves an adjustment requirement because the sensor is to be directed on to the cooking zone in targeted relationship therewith.
DE 195 02 935 A1 describes an apparatus for locating a cooking vessel which is provided with an active transmitter. A plurality of antennae are arranged in a distributed array at the cooking appliance, more specifically under the glass ceramic plate or hob thereof, whereby the intention is to be able to establish the cooking location over which the cooking vessel in question is disposed. The transmitter transmits for example temperature data to the cooking appliance, for which purpose it has a temperature sensor. A battery or an accumulator is required for the supply of power for the transmitter.
It is assumed in DE 195 02 935 A1 that the cooking vessels used are metal. If the cooking vessels used consist of a different material, the field line configuration changes considerably so that it becomes difficult to detect the position of the cooking vessel. Problems occur in particular if the intention is to be able selectively to use cooking vessels of metal and glass or ceramic.
If, in DE 195 02 935 A1, a plurality of cooking vessels with transmitters are used at the same time on the cooking appliance, difficulties are then encountered in terms of evaluating the individual transmitter signals. It is therefore proposed that the transmitters should additionally be provided with a receiver which detects whether an adjacent pot is transmitting at the same time. That means that the cooking vessel becomes even more expensive.
DE 94 16 779 U1 discloses a sensor-controlled glass ceramic cooking location unit. It comprises a cooking assembly which is suitable for an infra-red sensor, a glass ceramic cooking surface or hob, and a radiant heating source arranged beneath the glass ceramic cooking surface or hob. The cooking assembly corresponds with an ancillary electronic assembly by way of an infra-red path. The electronic ancillary assembly interchanges cooking data with an electronic system of the cooking hob, in which case the radiant heating source is controlled in the proximity of the cooking process. The ancillary assembly takes up space on the glass ceramic cooking surface and must be exactly oriented with the respectively associated cooking assembly. An identifying characteristic of the cooking assembly cannot be transmitted in this case.
In the above-mentioned state of the art there is also the disadvantage that articles or coatings or coverings which are introduced into the respective wireless transmission path can considerably disturb transmission.